Yes. Create a new material. You could start by copying the existing marble material. Open the material settings box
Options>Element Attributes>Materials
Duplicate the one closest to what you want such as the marble material
On the Exposure to Light tab Adjust the two Transparency sliders to get the effect you want. The preview window in the upper left corner will show real-time changes as you move the slider settings.
Erika
Architect, Consultant
MacBook Pro Retina, 15-inch Yosemite 2.8 GHz Intel Core i7 16 GB 1600 MHz DDR3
Mac OSX 10.11.1
AC5-18
Onuma System
"Implementing Successful Building Information Modeling"